Fabrication of sub-150 nm structures by two-photon polymerization for plasmon excitation

Two-photon polymerization (2PP) has attracted tremendous attention in fabrication of micro- and nanostructures during the last two decades because of its great capabilities in achieving structures with high resolution almost without geometric constraints. Nanofabrication by 2PP allows to generate feature sizes below the diffraction limit of the laser wavelength, so it is very attractive for application in production of 2D and 3D photonic devices. However, it gets increasingly challenging when it comes to structures below 150 nm. In this work, smooth structures with sub-150 nm wide lines and dots are realized via 2PP on a glass substrate.